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Topic: How can a b/w photo's thumbnail be in colours? (Read 5372 times)

Obviously this photo began life as a colour picture, and only then was converted into black & white. But it is a mystery to me how Explorer and several photo editors can display the thumbnail in colours. Of course the photo is b&w when I open it, but even when copied, the new thumbnail is still in colours. I wonder if a photo somehow is carrying a thumbnail photo of itself? I have never seen this before - but of course I very seldom have any black & white pictures. Actually, in this case as in most cases, I think I would prefer the colourful "orange" version ;-)Edited:I have not edited this photo; it was downloaded in black & white.

I actually have a picture on my computer that is the exact opposite. It was a black and white photo, and if I remember right, the exact steps I took were, 1. right click on the image in my browser and click copy, 2. paste into Photoshop and colorize it, and 3. save the image. Now the thumbnail in windows explorer is black and white, while the actual image is in color. I have never had this happen any other time.

(on a side note, your computer spells October weird. I'm from America, and only speak english, so if it is a foreign thing, that would explain it.)

The metadata inside of some image formats contains a thumbnail (or stamp). This information is entirely separate and distinct from the actual image itself, but is formed when the photograph is taken.

Not all editors deal with stamps (thumbnails) or not all editors deal with them properly.

When I wrote the Super Simple Photo Resizer, I came across this issue, and instead of simply not dealing with it, in at least some case (IIRC) I delete the stamp/thumbnail from the image file entirely. There are very good reasons to do this...

Imagine you're at home, getting out of the shower, and your spouse snaps a photo of you. While you don't want to post full frontal nudity of yourself, perhaps the facial expression is really funny, and you want to share that. So, you crop the photo and email or upload it...

Now, if the software didn't erase the stamp, you've just sent that original stamp of your naked body around. Not good. And probably not what you'd intended to do.

Anyways, that's a bit long for the simple explanation. -- Stamps and image data are not the same.

Oh - don't forget to check the "thumbs.db" file as it can contain cached data. You can safely delete that. If you've deleted the EXIF data, then the stamp is likely gone, but still in the thumbs.db file.

(That sounds like the issue - though I'm certain there are other ways for the wonderful world of computing to melt our minds! )

Imagine you're at home, getting out of the shower, and your spouse snaps a photo of you. While you don't want to post full frontal nudity of yourself, perhaps the facial expression is really funny, and you want to share that. So, you crop the photo and email or upload it...

Now, if the software didn't erase the stamp, you've just sent that original stamp of your naked body around. Not good. And probably not what you'd intended to do.

Imagine you're at home, getting out of the shower, and your spouse snaps a photo of you. While you don't want to post full frontal nudity of yourself, perhaps the facial expression is really funny, and you want to share that. So, you crop the photo and email or upload it...

Now, if the software didn't erase the stamp, you've just sent that original stamp of your naked body around. Not good. And probably not what you'd intended to do.

Imagine you're at home, getting out of the shower, and your spouse snaps a photo of you. While you don't want to post full frontal nudity of yourself, perhaps the facial expression is really funny, and you want to share that. So, you crop the photo and email or upload it...

Now, if the software didn't erase the stamp, you've just sent that original stamp of your naked body around. Not good. And probably not what you'd intended to do.